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Financial Instruments - Summary of Investments (Detail) - USD ($) $ in Thousands | Jun. 30, 2023 | Dec. 31, 2022
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Short-term, Municipal Bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Total short-term investments (available for sale), Cost |  | $ 3,016
Total short-term investments (available for sale), Gross Unrealized (Loss) |  | (22)
Total short-term investments (available for sale), Fair value |  | 2,994
Short-term, Non-governmental Debt Securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Total short-term investments (available for sale), Cost | $ 217,884 | 222,575
Total short-term investments (available for sale), Gross Unrealized Gain |  | 37
Total short-term investments (available for sale), Gross Unrealized (Loss) | (2,751) | (2,880)
Total short-term investments (available for sale), Fair value | 215,133 | 219,732
Short-term, Treasury and Federal Agencies [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Total short-term investments (available for sale), Cost | 215,761 | 179,068
Total short-term investments (available for sale), Gross Unrealized Gain |  | 6
Total short-term investments (available for sale), Gross Unrealized (Loss) | (2,790) | (2,485)
Total short-term investments (available for sale), Fair value | 212,971 | 176,589
Short-term Investments [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Total short-term investments (available for sale), Cost | 433,645 | 404,659
Total short-term investments (available for sale), Gross Unrealized Gain |  | 43
Total short-term investments (available for sale), Gross Unrealized (Loss) | (5,541) | (5,387)
Total short-term investments (available for sale), Fair value | $ 428,104 | $ 399,315

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